LAPAROSCOPY: OPERATING ROOM OR OFFICE

INTRODUCTION

The history of "office" laparoscopy is very interesting. The first known laparoscopy was performed in Europe in 1910. The first reference to "office" laparoscopy under local anesthesia was reported by Dr. Short in the British Medical Journal in 1925. In the 1970s laparoscopy using local anesthesia was performed by Dr. Hulka in 1973 when he performed clip sterilization. In addition, John Fishburne, M.D. in Oklahoma and Jefferson Penfield, M.D. in Syracuse, New York, as well as Emmet Lamb, M.D. at Stanford University were all performing laparoscopy using local anesthesia in outpatient settings. Between 1978 and 1980 during my reproductive endocrinology fellowship at Stanford University I performed well in excess of 100 diagnostic laparoscopies using local anesthesia in the Outpatient Clinic Department Procedure Room. We used Diazepam and Meperidine intravenously, as well as Xylocaine for anesthesia. In the 1980s Beverly Love, M.D. from Alabama began performing many outpatient laparoscopic sterilizations. It was estimated in the early 1980s that approximately 4% of gynecologists performed sterilization using local anesthesia. In 1990 Poindexter, et al. reported on 3,000 outpatient laparoscopic sterilizations. Internationally, laparoscopy using local anesthesia has been the standard approach for tubal ligation in India for many years. In 1995 "office" laparoscopy under local anesthesia (OLULA) was widely proclaimed as the next great transition in gynecologic surgery. Clearly, however, this is not a new approach to laparoscopy, but one which is undergoing a resurgence in interest.

The most stated reason for performing "office" laparoscopy is cost, with the estimated cost being approximately 25% that of surgery performed in the regular operating room. In addition, newer technology with smaller fiberoptic laparoscopes and STEP trocars, as well as smaller operating instruments have made this surgery easier for patients. In addition to these two most important reasons for performing "office" laparoscopy, other stated reasons have been patient preference because of a less intimidating setting, greater convenience, absence of general anesthesia, reduced risk, reduced postoperative pain, and shorter recovery period.

The new technology which has increased the feasibility of "office" laparoscopy includes development of the minilaparoscope by Origin Medical Systems in Palo Alto, California, the microlaparoscope by Imagyn Medical, Inc. in Laguna Niguel, California, and the optical catheter by Medical Dynamics, Inc. in Englewood, Colorado. All of these laparoscopes are small fiberoptical instruments less than two millimeters in diameter. The STEP trocar which was developed by InnerDyne Medical, Inc. in Sunnyvale, California has also been attractive instrumentation for many performing "office" laparoscopy.

CURRENT STATUS OF ROUTINE LAPAROSCOPY

The current status of routine laparoscopy is that it can be performed in hospital main or outpatient operating rooms, outpatient surgery centers, or procedure rooms located in appropriate facilities. Current capabilities include diagnosis and chromotubation, as well as therapeutic intervention for almost all benign gynecologic procedures and some oncologic diagnosis, therapy and monitoring procedures. Appendectomy can also be performed and ART procedures can also be completed with or without adjunctive therapeutic procedures. Diagnostic and operative laparoscopy under general anesthesia has now proven its efficacy, safety, and short recovery time in almost all gynecologic situations and is rapidly replacing laparotomy for management of almost all gynecologic conditions. The few exceptions include major gynecologic malignancies and exceedingly large uterine or adnexal masses, or severe uterine abnormalities.

The current status of "office" laparoscopy is that the "office" is usually a procedure room in a hospital or a surgery center, and sometimes a procedure room within a physician's office. The Webster New Universal Unabridged Dictionary definition of "office" is "the building, room, or series of rooms in which the affairs of a...professional person...are carried on". The definition for operation is "any surgical procedure performed with or without the aid of instruments, usually to remedy a physical ailment or defect". The definition for outpatient is "a nonresident patient; one who is not an inmate of a hospital, but receives medical attention from it". Given these definitions one can make an argument that the "O" in OLULA which is meant to stand for "office" could more appropriately stand for operative or outpatient since the actual location and circumstances under which "office" laparoscopy is performed more closely approximates an operating room or an outpatient setting than it does an office. A strong argument can be made for dropping the "O" altogether, and using the acronym LULA -- laparoscopy under local anesthesia -- to avoid misperceptions about the setting in which the procedure is performed. This convention will be followed.

Current capabilities of "office" laparoscopy include diagnostic procedures for all benign gynecologic conditions and for oncology diagnosis and monitoring, as well as chromotubation. Therapeutic procedures which have been performed include tubal ligation, second-look laparoscopy for adhesions, draining of ovarian cysts, and ART procedures. Efficacy has been demonstrated for some, but not all, procedures. For example, minimal endometriosis and adhesions may be treated, but moderate or severe conditions have not been treated. It would appear at this time that the primary role for LULA is diagnostic procedures only or therapeutic procedures requiring minimal operative intervention.

Procedures currently being developed for LULA include appendectomy and herniorrhaphy. Procedures currently not suitable for LULA include extensive or primary lysis of adhesions, invasive endometriosis, adnexal masses, adhesive bowel disease, myomas, surgery lasting more than one hour, surgeries with moderate or greater potential for significant blood loss, and patients with severe or acute pain.

ISSUES ASSOCIATED WITH LULA

It has been stated that LULA enjoys much higher patient acceptance than routine laparoscopy. One advantage is that the patient only has to remain nil per os (NPO) for six hours prior to the procedure. However, this carries a disadvantage of resulting in more difficult visualization because of a less well prepared bowel and the potential for more serious sequelae should bowel injury occur. In addition, it has been maintained that LULA is associated with less paperwork. However, this carries a greater chance of error or omission on the part of staff who may not have reviewed the medical record as carefully. In addition, fewer health care professionals are involved with LULA since a separate facility is not required. This can result, however, in less skilled assistance, on average, since in outpatient surgery centers personnel tend to be highly trained and sophisticated since they are only dealing with operations. Utilization of "office" staff for surgical procedures will result in less trained individuals assisting at the surgery. It is also stated that patients are less anxious because they do not have to undergo general anesthesia, but some patients will be more anxious because of the fear of pain and the concern over potential complications in an "office" setting.

Preparation for Surgery

Advantages of LULA include easier scheduling and less documentation prior to the operation, as well as the need to interact with fewer personnel since the recovery room nurse and anesthesiologist are not involved. However, as noted above, this increases the probability of missing some important information and creating an error of omission. The patient should be selected following careful clinical history and performance of the "belly test" in which the lower abdominal wall is elevated by the surgeon and the patient asked if she can tolerate this level of discomfort for approximately 30 minutes. Patient selection is critical for the success of LULA.

Anesthesia

The promoted advantages of LULA are that there are no anesthesiologist's costs. However, this definitely could be one situation in which "you get what you pay for". The absence of general anesthesia certainly can reduce some risks associated with surgery. However, the patient does experience more discomfort, a fact readily admitted by proponents of LULA. In addition, since mobilization of viscera causes discomfort, the amount and degree of mobilization can be limited by the patient's discomfort. The degree of Trendelenburg position and the volume of pneumoperitoneum can also be limited by patient discomfort. Importantly, the duration of the procedure, the use of energy sources, and size of puncture sites can all result in surgical limitations being created which would not occur if the patient were under general anesthesia using routine laparoscopic instrumentation. It is claimed that patients undergoing LULA have quicker discharge postoperatively because they do not have a general anesthetic. It is not yet proven that this is true in prospective controlled studies, and if there is a difference the clinical significance has not yet been demonstrated. It is my impression from my experience, however, that patients do recover somewhat faster from the anesthesia following LULA. However, it is not invariably true that the increase in the recovery rate is clinically meaningful and more than offsets the increased discomfort which occurs during the procedure. Some proponents of LULA have claimed that they perform fewer preoperative tests prior to LULA than they would for general anesthesia. It is not clear why this is so. Preoperative tests should be performed based on the patient's overall clinical situation and should only rarely need to be altered by the anesthetic approach.

Anesthetic Medications

The medications utilized for LULA are in standard use. These include analgesics such as meperidine 50 to 100 mg intramuscularly, fentanyl 100 Fg intravenously, and sedatives such as diazepam 10 mg by mouth or 2 mg intramuscularly, or midazolam 5 mgm intravenously. Disadvantages of these medications include primarily the impact on the cardiorespiratory system which can lead to respiratory embarrassment and/or arrest and in serious situations to cardiac arrest. In addition, all medications carry the potential for allergies and side effects. Atropine is usually given 0.4 mg 30 minutes preoperatively to help prevent vasovagal attacks, but this medication can also be associated with side effects. Local anesthetics also can result in cardiorespiratory complications and potentially allergies and/or side effects. Some surgeons use 5 mL lidocaine:bupivacaine 50:50, others straight lidocaine. Medications need to be carefully titrated before and during the procedure to obtain the optimal balance among patient comfort, surgeon capability, and anesthetic safety.

Conscious Patient

The fact that the patient undergoing LULA is conscious is frequently stated to be a major advantage since the patient can talk to the surgeon. However, the patient's mental status is not entirely normal secondary to the medications which she is taking, and the stress which she is undergoing during the surgery. While chronic pain mapping has been claimed to be a unique application of LULA, the long-term efficacy of such an approach in terms of pain resolution is yet to be confirmed by prospectively randomized trials with different investigators. It is possible for the patient to have intraoperative pain unrelated to her usual pain condition, and this can confound the findings. It is a stated advantage that the patient can inform the surgeon if she is uncomfortable. However, this also results in the surgeon having to modify the surgical procedure based on the patient's comfort level. This may limit the manipulation of viscera and visualization achieved, limit the amount of therapeutic intervention performed, and require the surgeon to work faster and potentially less safely or skillfully than he or she would otherwise, and also potentially lead to the need to discontinue the operation prematurely. It is recognized by essentially all those performing this surgery that, even with careful attention to the technical details, intraoperative comfort can never approach that of general anesthesia. It has also been claimed that there is an advantage to the patient viewing the progress of her operation. However, this potentially could create increased anxiety or even panic attacks in the patient and result in her misinterpretation of the operation's proceedings and/or findings because of her altered mental status and the unusual environment during surgery. It has been claimed that the patient participating in the surgery is an advantage for the patient and potentially the staff, although such participation is obviously a distraction to the surgeon and the operating room staff who need to be focused on the operative procedure.

Laparoscopy Techniques

In performing laparoscopy it has been stated as advantageous that LULA patients do not require a running intravenous line, although some surgeons do place a heplock, and that patients do not require a bladder catheter. This has a potential disadvantage, however, of not having intravenous access should this be needed in an emergency situation, and also potential increased risk of bladder injury if the bladder is not completely emptied by the patient prior to the surgery. Another commonly stated advantage is the lack of an anesthesiologist. However, this results in not having available the skills and services which are provided by the anesthesiologist. There is no ability to proceed immediately to operative laparoscopy and/or laparotomy in case of altered intraoperative findings or emergency.

The patient's discomfort can be controlled by "active insufflation" of the abdomen which involves increasing or decreasing the amount of pneumoperitoneum depending on the patient's discomfort. This has the disadvantage of resulting in an inconsistent pneumoperitoneum and variable visualization of the pelvis, as well as a distraction for the surgeon in having to monitor the pneumoperitoneum in addition to monitoring anesthetic medications and talking with the patient while operating.

Smaller 2 mm instruments are now available for biopsy, adhesiolysis, and coagulation. However, these instruments have much more limited utility than 5 mm instruments and are also more fragile and can break easily.

It has been claimed that there is reduced operating time with LULA, but again this has not been proven for matched populations of patients prospectively randomized. Some surgeons promoting LULA have mentioned the development of new organ manipulation techniques in order to reduce pain during LULA. The need for these techniques emphasizes that patients have minimal tolerance for incorrect or sloppy technique during LULA and that surgeons must be extremely gentle and relatively slower in manipulation of pelvic organs.

It has also been recommended by some that nitrous oxide be used rather than carbon dioxide because it is less irritating and results in less discomfort and vagal stimulation. Volumes as low as 500 mL for the pneumoperitoneum have been recommended. However, with nitrous oxide electrosurgery cannot be used and with the smaller pneumoperitoneum visualization is generally not as favorable. There are also other safety concerns with nitrous oxide.

Visualization at Laparoscopy

Many surgeons are enthusiastic about the smaller optical fiberscopes which clearly have markedly improved optical quality compared with prior similar instruments. However, these instruments still do not provide an image as good as a rigid lens laparoscope only 3 mm in size, and not nearly the same quality as the 5, 7, and 10 mm laparoscopes. The smaller endoscopes are capable of being utilized to view the entire abdominopelvic cavity. However, there is a much smaller field of view which mandates much more movement of the endoscope to view the entire abdominopelvic cavity, increasing the chance of missing some area, reducing perspective on the pelvic and abdominal structures, and also requiring longer to view the entire abdominopelvic cavity. In addition, the smallest drop of blood on the endoscope can result in an inability to see anything.

Postoperative Care

Postoperatively LULA patients are stated to have a shorter recovery time, require fewer personnel (for example, an anesthesiologist) and less postoperative care. However, this carries the disadvantage of having less ability to diagnose postoperative complications and an increased chance of sending the patient home with a complication not being detected. It has also been claimed that the patient returns to work and the activities of daily living sooner following LULA, but again there are no prospectively controlled studies of matched populations which demonstrate a clinically meaningful difference.

Ancillary Equipment for Safety

It has been stated by proponents of LULA that the following equipment is needed: continuous automated blood pressure monitor, continuous monitoring of cardiac electrical activity, pulse oximeter, Ambu bag with oxygen, anesthetics, sedatives, analgesics, reversal agents, and finally a crash cart with defibrillator, intubation equipment, and Atropine and other essential drugs. Clearly this is equipment which the average gynecologist does not have in his or her office, or utilize on a routine basis. This increases the probability that their use, if needed, will be less than optimal.

Safety

A commonly stated advantage of LULA is that there is no general anesthesia, and that the operation is therefore safer. However, intravenous anesthesia can be as dangerous as general anesthesia, especially when utilized by less skilled practitioners. Importantly, since there is no anesthesiologist the skills of an anesthesiologist will be not be available if an emergency situation occurs.

It has been claimed that the smaller instruments produce less trauma and pain, and therefore are also safer. This is potentially true since a smaller hole inadvertently placed within a blood vessel or bowel would appear to be better than a larger hole made by larger instruments. However, the smaller instruments and smaller endoscopes also result in less ability to visualize structures as well, and less ability to manage complications endoscopically.

It has also been suggested that the fewer new and unknown health care providers seen by a patient undergoing LULA, since they are in their own surgeon's office, is an advantage. However, this could potentially result in a greater chance of error of omission. In addition, there is less regulation than in an operating room, potentially less education of staff, less peer review of outcomes, and less

experience with emergencies. Additionally, operating rooms are required to have emergency generators in case of power loss, whereas, most physician's offices do not. These are all situations which could clearly decrease the potential safety for the patient. It is not at all clear that LULA is safer than general anesthesia in an operating room. The converse could, in fact, be true.

Cost

Claims of marked cost savings realized through LULA are impressive and important in today's medical economic climate. It is generally stated that LULA can be performed for $1,000 to $3,000 total cost, which is about 25% of routine hospital based laparoscopy costs. However, the cost situation is usually oversimplified. The capital equipment required to perform LULA costs between $5,000 and $25,000. Facilities to sterilize instruments and maintain and/or repair laparoscopy equipment are needed. The office must also replace equipment as it becomes broken. Any equipment which is purchased must be depreciated. Additionally, supplies have to be provided for each case. Large expenses usually covered in a hospital operating room or outpatient surgical center fee include pre- and postoperative personnel, and intraoperative nurses and surgical assistants. In the case of LULA, the surgeon must provide their own staff for pre- and postoperative care, as well as a nurse to monitor the patient's anesthesia, a surgical assistant, a scrub nurse, a video nurse, and an individual to take care of the equipment. In addition, the space in which LULA is performed must be rented or amortized and capital costs of room setup must be taken into account and amortized. Special equipment which must be purchased and frequently replaced include CPR equipment and drugs associated with this equipment. In addition, staff have to be trained, retrained, and undergo continuing medical and nursing education in operating room procedures, safety considerations, etc. It is also important to recognize that fiberoptic endoscopes are far more expensive per case than rigid lens endoscopes, and this will tend to increase the cost of laparoscopy. The surgeon performing LULA must assume liability both professionally and also within the business setting for the performance of surgery in the office. This will results in an added expense to insurance policies. Finally, the surgeon must assume the costs of ensuring that all federal, state, and local regulations and laws are adhered to, and continue to be adhered to as they are updated.

It has been claimed that insurance payors will rush to cover LULA rather than outpatient surgery center facilities because of decreased cost. However, other factors such as perceived patient acceptance and concern about safety and experimentation by payors may well limit acceptance of LULA. Such a situation has been reported in Minnesota.

Any cost savings due to performing LULA have to be offset by the extra costs involved in performing a second laparoscopy under general anesthesia in the operating room to treat surgical conditions that could not be performed at the time of LULA. Other patient associated costs such as time lost from work also need to be factored into these second surgery costs.

Medicolegal Liability

During LULA the patient is awake and viewing a video monitor. The patient's perspective of what happens during the operation may or may not be accurate, and in the case of unexpected or unfavorable outcomes may increase the surgeon's medicolegal liability. In addition, there are numerous regulations regarding facilities in which laparoscopy can be performed, maintenance of equipment, certification and training of personnel, and ongoing medical education. Should any untoward events occur in an office the surgeon would have to assume responsibility for any and all of these multitudinous regulations. These include OSHA regulations and also in California specific regulations with regard to the performance of any office procedure using anesthesia.

Should a complication occur there is clearly less support to recover from the problem than one would have in a routine laparoscopy situation. This includes less facility support, less equipment, and less highly skilled personnel. In particular, personnel having to manage cardiorespiratory and possibly surgical complications or emergencies would have much less training and experience than those which would be available during a routine laparoscopy. The surgeon would have to prove that adequate preparation and support for emergency situations had been provided if an untoward outcome occurred.

A major problem of LULA is the potential trivialization of a surgical procedure, namely laparoscopy, to the patient and family in describing the advantages of LULA compared to routine laparoscopy. Such trivialization of the procedure can dramatically change a patient's expectations of her experience and the outcome. This could affect the surgeon's perceived liability should the procedure not go as expected.

Regulations

California bill AB595, effective July 1, 1996 "was motivated by a concern that surgeries and other procedures using general anesthesia or anesthesia in levels which would inhibit a patient's protective reflexes were being performed in unregulated settings, such as physicians' offices and outpatient surgery centers in a manner which could prove injurious to a patient's health. Accordingly, under the new law, no physician or surgeon may perform procedures using the specified levels of anesthesia in.....an "outpatient setting", unless it is in full compliance with AB595".

AB595 applies to all "outpatient settings" defined to be "any facility, clinic, unlicensed clinic, center, office, or other setting that is not part of a general acute care facility, as defined in section 1250, and where anesthesia except local anesthesia or peripheral nerve blocks, or both, is used in compliance with the community standard of practice, in doses that, when administered, have the probability of placing a patient at risk for loss of the patient's life-preserving protective reflexes". Under AB595, an outpatient setting does not include, "any setting where anxiolytics and analgesics are administered when done so in compliance with the community standard of practice, in doses that do not have the probability of placing the patient at risk for loss of the patient's life-preserving protective reflexes".

All outpatient settings will be under the oversight of some authority which can monitor the setting for quality and safety.

If a cardiorespiratory complication of use of anesthesia during LULA occurs in California in an unlicensed setting, it might well be construed that the physician is in violation of this regulation. The surgeon would then be subject to penalties for breaking this law, in addition to any medicolegal liability. Other states may have similar laws, or may pass them in the future, placing office laparoscopy settings under strict regulation and/or exposing the surgeon to additional liability.

Outcome Data

While claims have been made regarding the equivalent outcome from LULA compared with routine laparoscopy there are no reported well performed studies which demonstrate equivalence of outcome. No authors are claiming superiority of surgical results over routine laparoscopy.

INDICATIONS FOR LULA VERSUS ROUTINE LAPAROSCOPY

It appears at this time that the use of LULA for conscious pain mapping is a legitimate and unique application of LULA. Longer term followup studies of outcomes are still required, however to document the effectiveness of conscious pain mapping.

Useful Indications for LULA in Selected Patients

LULA may become the approach of choice for the initial diagnostic laparoscopy in patients who have abdominopelvic pain, endometriosis, pelvic inflammatory disease, ectopic pregnancy, or suspected rupture of the corpus luteum. LULA also could be beneficial at the time of second-look laparoscopy to evaluate the patient for adhesions or results of neosalpingostomy. It may also be appropriate for monitoring a disease process, such as endometriosis or carcinomatosis, or the monitoring of concomitant hysteroscopic procedures such as septum resection or intrauterine myomectomy. LULA is already being utilized for ART procedures. Additionally, LULA may be appropriate in research protocols which are developed to monitor the progress of disease and/or its treatment.

LULA Not Indicated

LULA is not indicated for any procedure in which extensive disease is expected or more than minimal operative intervention is expected based on clinical history, physical, preoperative evaluation, and probable overall disease management plan. It also should not be utilized in cases in which the patient is already in acute pain when she presents, or if the patient is uncooperative and/or has a problematic mental status.

LULA Contraindicated

LULA is contraindicated in any patient in whom there is a contraindication of routine laparoscopy and in those with an enlarged uterus (greater than 12-14 weeks), in patients with multiple abdominal scars, obesity, or in which a routine laparoscopy is already planned.

CAVEATS FOR LULA

LULA is a procedure whose success is very operator dependent. It requires a properly trained surgeon with a clear understanding of the role of LULA in gynecology today. The facility must be properly equipped to meet all federal, state, and local regulations. Equipment needs to be of adequate quality to perform LULA. Additional equipment for emergencies must also be available.

Properly certified, trained, and educated personnel are mandatory. This includes their ability to participate constructively in the operating room and also to perform needed functions in case of emergency.

Systems need to be in place to ensure that the patient proceeding to LULA has undergone all of the appropriate preoperative testing, investigation, and informed consent to enable her to undergo the procedure safely. Intraoperative systems to ensure the smooth functioning of the procedure are required, as well as emergency systems in case of intraoperative complications or problems such as equipment failure or loss of power.

The surgeon and his or her assistants must have a comprehensive understanding of anesthesia and the agents which they are utilizing in both routine and emergency situations.

During the operation the surgeon needs to recognize his or her responsibility to communicate with the patient, and to be responsible for many more aspects of the operating room environment than he or she would be during routine laparoscopy. LULA is much less forgiving because the patient is awake and proper technique and attention to detail is mandatory throughout the procedure.

HYPE VERSUS REALITY

There has been a great deal of hype regarding LULA. My conclusions regarding LULA at this time are as follows:

1)The hype claims that LULA is new. In fact, it is almost 100 years old and now being retooled for a new medical environment.

2)LULA is claimed to cost only 25% of routine laparoscopy. The reality is that LULA is much cheaper than routine laparoscopy and this will drive its widespread application. But there are also many hidden expenses which are significant and must be accounted for in pricing this procedure. Currently many of the costs associated with LULA are probably being subsidized by other aspects of the medical practice. It is very worrisome to see LULA being touted in the media and promoted at costs to third party payors and others which are less than those which can be sustained over the long term. Such inappropriate promotion will eventually hinder the implementation and utility of LULA, to the detriment of patients and physicians.

3)The hype is that there is widespread application for LULA at this time. In fact, the only unique application currently identified is that for conscious chronic pain mapping. For some other applications LULA appears appropriate.

4)The hype about LULA is that it is much safer than routine laparoscopy. However, at this time there is no demonstrated difference in safety, and in fact complications are potentially riskier because of the less controlled environment in which the surgery is being performed.

5)The hype is that LULA is a patient-driven procedure, but the major cause for its reemergence is cost considerations and the development of new technology.

6)The hype is that LULA will replace operating room laparoscopy. The reality is that LULA will likely become an important component of new diagnostic and therapeutic paradigms and algorithms, but that routine laparoscopy and operative laparoscopy will retain a very important role in gynecology for the foreseeable future.

7)The most dangerous hype of all is that LULA is just an operating room laparoscopy performed in an office. In fact, LULA is an operation that requires different equipment, different personnel, different training, different procedures, and a different perspective by the patient, surgeon, and staff. This is a procedure which has important new applications, but its role should not be exaggerated, nor its performance trivialized, during its development.

REFERENCES

Adamson GD and Martin DC (Editors). Endoscopic Management of Gynecologic Disease. Philadelphia:Lippincott-Raven; 1996

Feste JR. Outpatient diagnostic laparoscopy using the optical catheter. Contemporary OB/GYN 1995 Aug;54-63.

Jacobaeus HC. Ueber die Moglichkeit der Zystoskopie bei Untersuchung seroser Hohlungen anzuwenden. Muench med Wochenschr. 1910;57:2090

Love BR. Office tubal ligation: the protocol I use. OBG Management 1996 Apr;86-91.

Oskowitz SP, Berger MJ, Mullen L, Smalky M, Alper M, Thompson I. Safety of a freestanding surgical unit for assisted reproductive technologies. Fertil Steril 1995;63:874-9.

Palter SF. Moving laparoscopy into the office. OBG Management 1995 Sep;27-36

Palter SF, Olive DL. Office microlaparoscopy under local anesthesia for chronic pelvic pain. JAAGL 1996 May;3(3):359-64.

Schultz LS. Cost analysis of office surgery clinic with comparison to hospital outpatient facilities for laparoscopic procedures. Int Surg 1994;79:273-7.